Fluid-actuated jack



Oct. 3o, 192s. y 1,690,037. T. W. PEDERSEN FLUID CTUATED JACK 4Filed June 1. 1925 4 Sheets-Sheet 1 A 4 /6 l L Ef E I l z fzmfwz@ ocr. so, 192s. 1,690,037

T. W; PEDERSEN FLUID AcTUATED-JACK Filed 'June 1, 1925 .4 sheets-sheet 2 17g i6 P T. W. PEDERSEN FLUID ACTUATED JACK oef. 3o, 1928. 1,690,037

Filed June 1. 1925 4 Sheets-Sheet 3 I .7". l l 5 .Ima/@2r- '0a. 3o, 192s.

1,690,037 T. W. PEDERSEN FLUID ACTUATED JACK' 4 slm'e'cs-sheen;y 4

Filed June l, 1925 Inman/5777 oma'lfanfm ha/ZM af: y; .L w`

30 Fig. 4` is a. transverse section tothe main cy Psanaa og. so,

\ i :UNITED- s'rA'rss PATENT OFFICE.

.moms w.

NEDEBSEN, F NEW YORK, N. Y., ABSIGNOB. TO 011| JACK, INC., 0F NEW YORK, Y., A. CORPORATION 0F NEW YORK.

' FLUID-AOTUATED JACK.

Yapplicativa med :une 1, 1925. serial nefs-1,100.

l This inventionA relates to fluid actuated jacks, and more particularly to that type of Y, vpick which includes a self-contained reservoir for the, actuating fluid, together with pressuremeans for transferring the actuatuid 'fromv thereservfoir tothe jack cyliuder in which the stem o rates.A

The 'principal object o the resent inven- ,tion is to rovide a compact an easily manuln factured ]a.ck of this general type in which the number of parts is reduced to a minimum.

Another object of the invention is to provide a. jack in which the main cylinder, pump cylinder and reservoir are integrally formed.

15 A still'further object of the invention is to provide novel and advantageous means of guiding the stem in the cylinder and for preventing leakage where the stem projects from i the cyhnder.

25 in accordance with my invention;

Fig. 2 is a vertical section on the, line 2 2, Fig; -K ig. 3 is a.- sectional elevation onthe line 3 3, Fig. 1; and f on .the line ,'Ilg- 1- Wit reference lto the drawings, the )ack vvcomprises an integral -castin 1 'including a central main cylinder 2in w ich the stem 3 :15 of .the jack operates in welLknown manner.

The lower rtion of the casting is enlarged and is m e hollow-to provide a reservoir chamber 4 for an actuating fluid, and this chamber communicates throu h a channel 5 and port 6 with the bottom o a pump cylin? der 7 formed-in an integral bo 8 ofthe castin as clearly illustratedin Fig. 3. The ump cy inder7 connects through a port A9 an passage 10 with the bottom of the main cylinder 45H 3, and valves 11 and 12 control the-passa e of the fluliid1 cflrom tle frlesel'vxlir chamberto e pum eran omte umpcym er p cy lmder 3 as will ereinafter be more full 'It will noted that the channel 5 may be formed by drilling from the outside of the casting 1` into the bottom of the reservoir chamber 4; that the rt 6 may be formed by drillin through the ttom of the pump cylu inder into the said channel 5; and that the The invention further resides in certainl novel features and details of construction as .through a transverse chamber or recess 14, at

the inner end of which the port 9 is formed. The outer end of the channel `5 is closed in the present instance by a plug 15, while the outer endof the channel 10 is closed by means of a screw plug 16, the channel being sealed by a suitab e counter-bore provided for the head of said screw plug. The valve 11 consists of aball y restirg by gravity in the bottomof the pump cylin er v7 and normally closing theport 6, while the valve 12 consists also of a ball normally retained to its seat, closing the port 9, as shown in Fig. 4, through the medium of a spring 18 in the chamber 14, the sprin be ing confined between the valve 12 an the inner end of a tapered plug 19 threaded into the outer end of the chamber.

Thereservoir chamber 4 has further communication with the main cylinder 2 through a' passage 20 which enters the said cylinder at a point somewhat above the bottom, and the outer end of this passage 20 is normall closed by a manuall actuable valve 21 thr ed into a plug 22 w ich in turn is threaded into a port 1n the outer wall of the chamber 4. The

gasket 17 in the bottom of the' 'l plug 22 includes a lchamber for reception of y suitable packing 23, and a followerring 24 is threaded into the outer end of this-chamber and retains the packing in place. The valve 21, as clearly shown in Fig. 2, projects beyond the outerend of the follower V24 and is provided with suitable, projections `25 in th bottom of the mainl cylinder 2, asclearly shown in Figs. 2 and 3, has an enlarged bot-`v -tom (portion 28, and threaded into a counterbore recess in the outer end of sadwmain"l Cylinder 2 is a collar 29 which .slidably'fits the stem 3 and actsy withthe enlarged'iplortion .5.

is col- 28 to guide thestem in the cylinder. I* lar also cooperates with the enlarged portion 28 to revent the stem.from asising from thek cylin er when in the'- exten ed position fthe enlargement 28 engaging the under sde'of the said collar and retainlng it in the cylinder. A slot or.slo ts 28lis provi/decll in the e'n' largement to perinit free passage of fluid between the opposite sides thereof.

Outwardly of the collar 29 the main cylinder 2 is provided with an enlarged counterbored recess 30 for reception of suitable packing elements 31, and these elements are retained in place by means of a follower ring 32 threaded into a third counterbored recess 33 at the extreme top of the cylinder, the follower ring 32 functioning also to guide the stem 3 in the cylinder. As is customary, the upper end of the stem 3 has a reduced threaded portion for reception of a load-engaging head 34.

Operating in the pump cylinder 7 is' a plunger 35 having attached to the bottom or inner end thereof suitable packing elements 36, by means in the present instance of a screw 37, the plunger 35 having pivotally secured to the upper end thereof, which proJects out of the cylinder, a link 38, which link also pivotally connects with a lever 39 which is pivotally secured at 4() to the casting 1. This link 39 also has at the to a socket 'portion 41 for reception of a hand e lever, not shown, whereby the lever 39 may be oscillated around its pivot to thereby reciprocate the plunger 35 in the cylinder 7. The top of the cylinder boss 8 is provided with a counterbored recess 42 for reception of suitable packing material 43, and a follower ring 44 is threaded into the top of the recess to retain the packing in place.

The casting 1 further comprises an integral handle portion 45, by means of which thecasting may be easily gripped and held in position during the operation of the lever 41,'

the handle extendin from the casting 1 in a direction substantilly parallel to the direction which the handle lever assumes when inserted in the socket portion 41 of the lever 39 and to the plane in which the lever operates.

A port 46 extending from the outside of the casting into the chambe1=4 from the top of the enlarged portion which encloses said chamber provides for the admission of the actuating fluid to the reservoir chamber, and this passage 46 is normally closed by a.v tapered plug 47 threaded into the outer end of the passage. Y

O ration of the jack will be readily understoc by those acquainted with the art. With the parts as shown in Figs. 2 and 3, reciproation of the pump plunger 35 in the manner indicated resultsin a withdrawal of the actuating iluid from the chamber 4 into the pump. cylinder and a consequent discharge rom the pump cylinder into the main cylinder 2 below the stem 3. Transference of the liquid in this manner results in an elevation or' the stem 3 to the desired extent. When it is desired to lower the jack, the valve stem 21 is turned to open the port 20, which thereby permits the actuating Huid to flow back into the reservoir. V

f' and to form an additional To prevent undue outward movement of the similar lu 51 extending from the main cast-` ing 1 of t e jack, when the plunger 35 has attained its practical limit of outward movement.

rThe herein described construction provides a jack that is easily manufactured at comparatively low cost, involves a minimum number of parts, and is extremely efiicient in operation, and durable. The jack also possesses great strength and rigidity due in part to the multiple means of guiding the stem in ,the cylinder. y f' It will be apparent that there may be some modification without departure from the essential features of the invention.

I claim: Y

1. A uid operated jack comprising an in tegrally formed reservoir, base, main cylinder and pump cylinder; a movable stem in said main cylinder having an enlarged portion in the cylindrical surface of which are formed slots to permit free passage of fluid from one side thereof to the other; a threaded collar screwed into a recess in the outer end of the main cylinder and slidably fitting said stem thereby acting jointly as a guide therefor and as a stop for limiting its travel by engagement with said yenlarged portion; a plunger in the pump cylinder; and means for controlling the flow of Huid from the main cylinder to the reservoir.

2'. A" `fluid operated j ack comprising an invteg'rz'illy'i'ormedl reservoir, base, main cylinrder and' pump cylinder; a movable stem in the main cylinder havin a diameter smaller than the bore of said cy inder; an enlarged ortion -formed on the end of said stem slidably ttin the bore of the cylinder and having in t e cylindrical surface thereof slots permitting free passage of fluid from one side thereof to the other; a threaded collar screwed into a recess near the outer end of the main cylinder forming a guide for said stem anda stop to limit its travel by engagement with its enlarged end; packing washers in a second recess adjacent said collar; a follower ring screwed into a third recess adjacent the second to retain the packing washers ide for the stem; a plunger in the pump cy der; and means for controlling the flow of Huid from the main cylinder to the reservoir.

3. A fluid operated jackl comprising a reservoir, main cylinder; and pump cylinder; a movable stem in the main cylinder havin a diameter smaller'than the bore of Said cy der; an enlarged ortion formed on the end of said stem slidalblgn fitting the bore of the cylinder; passages ormed-in said enlarged portion to ermlt free How of fluid from one side thereo to the other; 'a collar detachably mounted near the outer end of the main cylinder forming a guide for said stem and a stop to limit its travel by engagement With its enlarged end; packing means adjacent said collar; and means for providing and controlling a flow of fluid from the pump cylinf der' to the main cylinder and from the main cylinder to the reservoir. Y

4. In a fluid operatedjack, the combination of a cylinder; a movable stem in said cylinder of smaller diameter than the bore of the cylinder; an enlarged portion on the end of said stem slidably fitting the bore of the Cylinder; passages formed in said'enlar ed pora tion to permit freerfflow of fluid rom one side thereof to the other; a guide ringslidably fitting the smaller portion of .said stem and detachably mounted near the outer end of saidcylinder; means for packing the outer end of the cylinder; a pump adapted to supply iiuid to said cylinder; a reservoir; passages connecting the reservoir with the pump and cylinder; and means for controlling the flow of fluid in said passages.

THOMAS W. PEDERSEN- f 

